U.S. patent number 7,879,277 [Application Number 12/467,582] was granted by the patent office on 2011-02-01 for method for forming hollow moldings having thin film on inner surface.
This patent grant is currently assigned to The Japan Steel Works, Ltd.. Invention is credited to Shoso Nishida.
United States Patent |
7,879,277 |
Nishida |
February 1, 2011 |
Method for forming hollow moldings having thin film on inner
surface
Abstract
The method employs a stationary mold having depositing recesses
equipped in its inside with a deposition element such as a target
electrode, and movable molds made slidable. A primary molding is
performed to form a body portion and a cover member to have joint
portions around their opening. The body portion left in the
vertically sliding mold is deposited after it was densely covered
with the depositing recesses. Next, the deposited body portion and
the cover member, as left in the molds, are registered and mold
clamped, and the molten metal is injected to integrated the joint
portions.
Inventors: |
Nishida; Shoso (Hiroshima,
JP) |
Assignee: |
The Japan Steel Works, Ltd.
(Tokyo, JP)
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Family
ID: |
39260355 |
Appl.
No.: |
12/467,582 |
Filed: |
May 18, 2009 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20090218716 A1 |
Sep 3, 2009 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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11529406 |
Sep 29, 2006 |
7744361 |
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Foreign Application Priority Data
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May 26, 2005 [JP] |
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P2005-153273 |
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Current U.S.
Class: |
264/250; 264/267;
264/263; 264/328.8; 264/255; 264/328.11; 264/328.7 |
Current CPC
Class: |
B29C
45/0062 (20130101); B29C 2045/0063 (20130101); B29C
66/54 (20130101); B29C 2045/0067 (20130101) |
Current International
Class: |
B29C
45/14 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2-38377 |
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Aug 1990 |
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JP |
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3047213 |
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Mar 2000 |
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JP |
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3326752 |
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Jul 2002 |
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JP |
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2004-136532 |
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May 2004 |
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JP |
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2004-338328 |
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Dec 2004 |
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JP |
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2006-224449 |
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Aug 2006 |
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JP |
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Other References
Japanese Office Action dated Feb. 15, 2008. cited by other .
Korean Office Action dated Sep. 28, 2007 for Application No.
10-2006-0093611. cited by other .
Chinese Office Action dated Jul. 3, 2009. cited by other .
Chinese Office Action issued in Application No. 200610141514.4,
dated Dec. 11, 2009. cited by other .
German Office Action issued in corresponding German Application No.
10 2006 044 933.9, issued on Sep. 22, 2010. cited by other.
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Primary Examiner: Lee; Edmund H.
Attorney, Agent or Firm: Sughrue Mion, PLLC
Parent Case Text
This is a divisional of application Ser. No. 11/529,406 filed Sep.
29, 2006, now U.S. Pat. No. 7,744,361, which is based on Japanese
Patent Application No. 2005-153273. The entire disclosure of the
prior application, application Ser. No. 11/529,406, is hereby
incorporated by reference.
This application is based on Japanese Patent Application No.
2005-153273, which is incorporated herein by reference.
Claims
What is claimed is:
1. A method for forming a hollow molding having a thin film on an
inner surface, the method comprising: molding a first semi-hollow
body using a stationary mold and a slidable movable mold, wherein
the slidable movable mold is in a first position; sliding the
slidable movable mold to a second position while leaving the first
semi-hollow body in the slidable movable mold; and molding a first
semi-hollow cover and a second semi-hollow body in the second
position using the stationary mold and the slidable movable mold;
depositing the thin film on an inner surface of the first
semi-hollow body while the slidable movable mold is in the second
position; and sliding the slidable movable mold to a third
position, where an opening of the first semi-hollow body registers
with an opening of the first semi-hollow cover while the first
semi-hollow body and the first semi-hollow cover are left in the
slidable movable mold and the stationary mold, respectively; mold
clamping the slidable movable mold to the stationary mold while the
slidable movable mold is in the third position; and injecting a
molten resin to joint portions of the first semi-hollow body and
the first semi-hollow cover so as to integrate the first
semi-hollow body and the first semi-hollow cover.
2. The method for forming the hollow molding according to claim 1,
wherein the semi-hollow bodies to be paired at the primary molding
are molded of individually different resin materials.
3. The method according to claim 1, further comprising: returning
the slidable movable mold to the first position and molding a third
semi-hollow body and a second semi-hollow cover; depositing the
thin film on the second semi-hollow body in the first position;
sliding the slidable movable mold to a fourth position where an
opening of the second semi-hollow body registers with an opening of
the second semi-hollow cover while the second semi-hollow body and
the second semi-hollow cover are left in the slidable movable mold
and the stationary mold, respectively; mold clamping the slidable
movable mold to the stationary mold while the slidable movable mold
is in the fourth position; and injecting a molten resin to joint
portions of the second semi-hollow body and the second semi-hollow
cover so as to integrate the second semi-hollow body and the second
semi-hollow cover.
4. The method according to claim 1, wherein the slidable movable
mold is provided with a cover molding core, a first body molding
recess, and a second body moving recess; and wherein the stationary
mold is provided with body molding core, a cover molding recess, a
first depositing recess, and a second depositing recess.
5. The method according to claim 4, wherein the cover molding core
is slidable in a horizontal direction and the first body molding
recess and the second body molding recess are slidable in a
vertical direction.
6. The method according to claim 4, wherein when the slidable
movable mold is in the first position, the first body molding
recess on the slidable movable mold is registered with the body
core on the stationary mold and the second body molding recess on
the slidable movable mold is registered with the second depositing
recess.
7. The method according to claim 4, wherein when the slidable
movable mold is in the second position, the second body molding
recess on the slidable movable mold is registered with the body
core on the stationary mold and the first body molding recess on
the slidable mold is registered with the first depositing
recess.
8. The method according to claim 1, wherein when the slidable
movable mold is in the third position, the first body molding
recess on the slidable movable mold is registered with the cover
member recess on the stationary mold.
9. The method according to claim 3, wherein when the slidable
movable mold is in the fourth position, the second body molding
recess on the slidable movable mold is reistered with the cover
member recess on the stationary mold.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for forming a hollow
molding integrated by jointing openings of a pair of semi-hollow
bodies and having a thin film deposited on the inner surface of at
least one semi-hollow body, and a molding apparatus to be employed
for executing the molding method.
2. Description of the Related Art
A molding having a thin film of several micron orders partially on
the inner surface of a hollow body is exemplified by a front lamp
or a tail lamp, which is attached to a vehicle. This lamp is
composed of a recessed body portion having an electric bulb, and a
lens unit integrally attached to the opening of the body portion.
The body portion is molded by an injection molding method, for
example, and is suspended in a deposition-dedicated vacuum tank by
means of a dedicated hanger while its unnecessary portion such as
an outer surface being masked. The body portion is then formed with
a thin film by the later-described deposition method. The body
portion is set again in a mold and is registered with a lens
portion molded separately so that they are jointed and integrated
by an injection molding method.
The deposition method for forming a thin film on the surface of a
substrate such as the body portion is known in the art. There are
known: the sputtering method, in which the thin film is formed by
arranging the substrate and the target in a confronting manner and
by applying and discharging a negative voltage of several KV to the
target in an argon gas atmosphere of several Pa to several tens Pa;
the vacuum deposition method, in which the film is formed by
housing the substrate and the evaporation source in a vacuum
container; the ion plating method, in which the vacuum deposition
is performed in an argon gas under a pressure of several Pa by
applying a negative voltage of several KV to the substrate; and the
chemical deposition method.
JP-B-2-38377 discloses a method for forming a hollow molding by an
injection molding. Specifically, the hollow molding forming method
includes: a primary molding, in which a pair of primary
semi-moldings are so formed by a pair of cavities formed by the
stationary mold and the slide mold as to have a joint portion
around their opening; and a secondary molding, in which the molds
are opened so that one primary semi-molding is left on the
stationary mold whereas the other primary semi-molding is left on
the slide mode, in which the slide mold is slid to the position
where the joint portions of the paired primary semi-molding are
registered, in which the molds are then mold clamped, and the joint
portions are jointed by injecting the molten resin thereto.
Moreover, Japanese Patent No. 3,326,752 discloses such one of the
molding method of JP-B-2-38377, that a guide portion is integrally
formed at the primary molding time on the inner side of the joint
portion or the abutting portion of one primary semi-molding, and
that the abutting portion of the other primary semi-molding is
guided for the secondary molding, when it is fitted on the abutting
portion of one primary semi-molding, by the guide portion of the
abutting portion of the one primary semi-molding. On the other
hand, Japanese Patent No. 3,047,213 discloses a molding method, in
which the hollow molding is formed as described above, by injecting
and filling the resin so that the angle made by the abutting
portion from the injecting and filling point at the secondary
molding time may be 90 degrees or less.
According to the forming methods described above, there arise many
problems because the substrate has to be formed in advance by the
injection molding method and has to be transferred into the vacuum
tank for the deposition. For example, the substrate is molded in
advance and is stored. Therefore, the substrate may be soiled on
its surface with hand or dust while being stored, so that it may
cause a deposition failure. In order to avoid this, the handling of
the substrate requires the highest care and raises the cost.
Further, the prefabricated substrate is once stored so that its
storage raises a management problem. In addition, the substrate has
to be once extracted from the mold before it is deposited, and has
to be again inserted into the mold before it is jointed, thus
lowering the productivity.
On the other hand, the injection molding method disclosed in
JP-B-2-38377, is advantageous not only in that the individual steps
can be automated to mass-produce the hollow moldings but also in
that even the hollow moldings of complicated shapes can be
manufactured. According to the invention of Japanese Patent No.
3,326,752, on the other hand, even with more or less deformations,
the abutting portions can be brought into fine abutment thereby to
raise an effect that the resin for the secondary molding has no
leakage. Moreover, the invention of Japanese Patent No. 3,047,213
is characterized in that its joint strength is so high that the
molten resin for the secondary molding can be molded even with less
injection portions. Thus, these inventions are effectively
practiced still at this time. The molding methods of the related
art, however, cannot form the thin film of the order of several
microns on the inner surface of the hollow molding.
SUMMARY OF THE INVENTION
The present invention contemplates to provide a molding method
having solved the aforementioned problems of the related art, and
has an object to provide a method for forming a hollow molding
having a thin film on its inner surface, which has any deposited
face contamination so that its quality is not deteriorated by the
deposition failure, which does not need any special storage
management, and which can be automatically molded with ease, and a
molding apparatus to be used for practicing that molding
method.
In order to achieve the above-specified object, according to the
invention, while the inner surface of the body portion molded by a
stationary mold and a movable mold made slidable is being left in
the recess of the movable mold, the body portion is covered with a
depositing chamber having a deposition element such as a target
electrode, a substrate electrode or a vacuum suction pipe therein
so that the deposition is performed in the mold.
In order to achieve the above-specified object, according to a
first aspect of the invention, there is provided a method for
forming a hollow molding having a thin film on its inner surface,
comprising: a primary molding comprising: molding a pair of
semi-hollow bodies by using a stationary mold and a slidable
movable mold; a depositioning comprising: driving the slidable
movable mold to a predetermined position while leaving the paired
hollow bodies molded at the primary molding in their individual
molds; and depositing the inner surface of at least one of the
paired semi-hollow bodies while being covered with a depositing
recess which is formed in the stationary mold and includes therein
a deposition element comprising a target electrode, a substrate
electrode and a vacuum suction pipe; and a secondary molding
comprising: driving the slidable movable mold to the position,
where the opening of the paired semi-hollow bodies registers, while
the paired semi-hollow bodies, at least one of which is deposited,
being left in the individual molds; mold clamping the slidable
movable mold; and injecting a molten resin to joint portions of the
semi-hollow bodies so as to integrate the paired semi-hollow
bodies. According to a second aspect of the invention, there is
provided a method for simultaneously forming a plurality of hollow
moldings each having a thin film on its inner surface, comprising:
a primary molding comprising: molding a plurality of pairs of
semi-hollow bodies by using a stationary mold and a slidable
movable mold; a depositioning comprising: driving the slidable
movable mold to a predetermined position while leaving the
plurality of pairs of hollow bodies molded at the primary molding
in their individual molds; and depositing the inner surface of at
least one of the paired semi-hollow bodies while being covered with
a depositing recess which is formed in the stationary mold and
includes therein a deposition element comprising a target
electrode, a substrate electrode and a vacuum suction pipe; and a
secondary molding comprising: driving the slidable movable mold to
the position, where the openings of the plurality of pairs of
semi-hollow bodies register, while the plurality of pairs of
semi-hollow bodies, at least one of which is deposited, being left
in the individual molds; mold clamping the slidable movable mold;
and injecting a molten resin to joint portions of the semi-hollow
bodies so as to integrate the plurality of pairs of semi-hollow
bodies. According to a third aspect of the invention, the
semi-hollow bodies to be paired at the primary molding are molded
of individually different resin materials.
According to a fourth aspect of the invention, there is provided a
molding apparatus for forming a hollow molding integrated by
jointing a pair of semi-hollow bodies around an opening and having
a thin film on the inner surface of at least one of the semi-hollow
bodies, comprising: a stationary mold comprising: a core and a
recess for molding the paired semi-hollow bodies; and a first
depositing recess and a second depositing recess disposed at a
predetermined spacing and including a deposition element comprising
a target electrode, a substrate electrode and a vacuum suction
pipe; and a movable mold comprising: a horizontally sliding mold
having a core coactive with the recess of the stationary mold; and
a vertically sliding mold having a first recess and a second recess
coactive with the core of the stationary mold, the first depositing
recess and the second depositing recess being sized to cover the
first recess and the second recess disposed in the vertically
sliding mold, respectively. According to a fifth aspect of the
invention, there is provided a molding apparatus for simultaneously
forming a plurality of pairs of hollow moldings integrated by
jointing pairing semi-hollow bodies around an opening and each
having a thin film on the inner surface of at least one of the
semi-hollow bodies, comprising: a stationary mold comprising: a
plurality of cores and a plurality of recesses for molding the
paired semi-hollow bodies; and a first depositing recess and a
second depositing recesses disposed at a predetermined spacing and
including a deposition element comprising a target electrode, a
substrate electrode and a vacuum suction pipe; and a movable mold
comprising: a horizontally sliding mold (having a plurality of
cores individually coactive with a plurality of recesses of the
stationary mold; and a vertically sliding mold having a first
recess and a second recess individually coactive with the core of
the stationary mold, and the first depositing recess and the second
depositing recess being sized to cover the first recess and the
second recess disposed in the vertically sliding mold,
respectively.
Thus, according to the invention, a pair of semi-hollow bodies are
molded by using a stationary mold and a slidable movable mold, and
the slidable movable mold is driven to a predetermined position
while leaving the paired hollow bodies molded at the primary
molding step, in their individual molds, to deposit the inner
surface of at least one of the paired semi-hollow bodies while
being covered with a depositing recess formed in the stationary
mold and having a deposition element such as a target electrode, a
substrate electrode or a vacuum suction pipe. In short, the paired
semi-hollow bodies are not taken out from the mold but are
deposited in the mold while being covered with the depositing
recess, so that the deposited face is not soiled on its surface
with hand or dust. It is, therefore, possible to provide a hollow
molding of an excellent deposited quality having the thin film on
its inner surface. Moreover, the deposition is performed in the
mold while the semi-hollow bodies are left in the mold, so that the
semi-hollow bodies need no storage management. According to the
invention, moreover, the slidable movable mold is driven to the
position, where the opening of the paired semi-hollow bodies
registers, while the paired semi-hollow bodies, at least one of
which is deposited, being left in the individual molds, thereby to
mold clamp the slidable movable mold, so that the paired
semi-hollow bodies are integrated by injecting a molten resin to
their joint portions. By using the molds, even the hollow molding
of a complicated shape having the thin film on its inner surface
can be automatically formed with ease.
According to another invention, on the other hand, a plurality of
pairs of semi-hollow bodies are molded by the primary molding step,
and the inner surface of at least one of the paired semi-hollow
bodies even pairing at the deposition step is deposited, and the
paired semi-hollow bodies at the secondary molding step are
integrated. In addition to the effects thus far described, the
plurality of hollow moldings each having the thin film on its inner
surface can be simultaneously produced to improve the molding
efficiently.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B are diagrams showing a molding apparatus according
to a first embodiment of the invention and presenting schematic
perspective views A and B of a stationary mold and a movable mold,
respectively, from the side of a parting line;
FIGS. 2A to 2J are diagrams showing the molding apparatus according
to the first embodiment and presenting top plan views A to J of
individual molding steps schematically.
FIGS. 3A to 3D are diagrams showing examples of the molds for
explaining the working principle of the invention and presenting
sectional views A to D of the individual molding steps
schematically; and
FIGS. 4A and 4B are diagrams showing a molding apparatus according
to a second embodiment of the invention and presenting schematic
perspective views A and B of a stationary mold and a movable mold,
respectively, from the side of a parting line.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Here is described a molding example of a molding article having a
thin film in its inside, which is formed by injection-molding a
cup-shaped body portion and a plate-shaped cover member for sealing
the opening of the body portion, by forming the thin film on the
inner surface of the body portion in the mold, and by sealing the
opening of the body portion with the cover member. An embodiment of
a molding apparatus of the invention is described at first. FIG. 1
presents perspective views schematically showing the molding
apparatus according to an embodiment of the invention. FIG. 1A is a
perspective view of a stationary mold 1, as taken from a parting
line side, and FIG. 1B is also a perspective view of a movable mold
20, as taken from the parting line side. In the shown embodiment,
the stationary mold 1 has a parting line face P formed into a
generally cross shape of a first vertically extending molding face
2 and a second horizontally extending molding face 10.
In the first molding face 2, first and second depositing recesses 3
and 4 for forming a vacuum chamber are formed at a vertically
predetermined spacing. These depositing recesses 3 and 4 are so
sized as to cover the later-described body molding recesses, and
are provided therearound with O-rings 5. When the depositions are
made by the sputtering method, for example, deposition elements
such as target electrodes or substrate electrodes are disposed in
the depositing recesses 3 and 4 thus formed, or vacuum suction
pipes or argon gas feeding pipes are opened in the depositing
recesses 3 and 4. Moreover, the openings of those electrodes or
vacuum suction pipes are connected at their openings to an
evacuating device 8, an inert gas feeding device 9 or a not-shown
power source device through hoses 6 and 7.
The second molding face 10 in the horizontal direction is provided,
at its position to register with the first and second depositing
recesses 3 and 4, with a body molding core 11 for molding the
cup-shaped body portion. The second molding face 10 is further
provided, as spaced at a predetermined distance from the body
molding core 11, with a cover member molding recess 12 for molding
the cover member. The body molding core 11 protrudes outward from
the parting line face P. As a result, the body portion is formed
into a cup shape. On the other hand, the cover member molding
recess 12 is slightly recessed from the parting line face P. As a
result, a plate-shaped cover member is molded. Around this core 11,
although not shown in FIG. 1, there is formed a bulge for molding
such a joint portion integrally with the body portion as will be
described in detail with reference to FIG. 3.
The movable mold 20 is composed of a horizontally sliding mold 22
so attached to a movable frame 21 as can be horizontally slid, and
a vertically sliding mold 30 so attached to the horizontally
sliding mold 22 as can be vertically slid. These molds 22 and 30
have their parting line faces P formed in a common plate. In the
embodiment shown in FIG. 1B, therefore, the horizontally sliding
mold 22 is horizontally divided so that the vertically sliding mold
30 slides vertically of FIG. 1B between the divided portions. The
horizontally sliding mold 22 thus formed is horizontally driven
integrally with the vertically sliding mold 30 by an actuator 24
which has its one end portion attached to a support member 23
horizontally extending from the movable frame 21. On the other
hand, the vertically sliding mold 30 is vertically driven
independently of the horizontally sliding mold 22 by an actuator 32
which has its one portion attached to a vertically extending
gate-shaped support member 31.
A cover member molding core 25 for forming the cover member is
formed on such one side of the parting line face P of the
horizontally sliding mold 22 of the movable mold 20 thus formed as
crosses the vertically sliding mold 30, and a clearance recess 26
for clearing the body molding core 11 when mold clamped is formed
on the other side. Around the cover member molding core 25, like
the body molding core 11, there is also formed the bulge for
molding the joint portion integrally with the cover member,
although not shown in FIG. 1B. In the parting line face P of the
vertically sliding mold 30, there are formed first and second body
molding recesses 33 and 34, which correspond to the first and
second depositing recesses 3 and 4 formed in the stationary mold
1.
The stationary mold 1 and the movable mold 20 thus far described
can be used to form the cup-shaped body portion and the
plate-shaped cover member by the primary molding operation, and the
body portion and the cover member can be integrated to form the
hollow molding by the secondary molding operation. An example of
the mold for explaining this molding principle is specifically
shown in FIG. 3. Specifically, this mold is composed of a
stationary mold 40 and a slide mold 45, and a body molding recess
41 of a predetermined depth for molding the body is formed at an
upper position in the parting line face P of the stationary mold
40, whereas a cover member molding core 42 of a relatively small
height is formed at a lower position. A small core 43 is formed
around and at a predetermined spacing from that core 42. The small
core 43 forms a jointing step portion around the opening of the
cover member. On the parting line face P of the slide mold 45, on
the other hand, there is formed a body molding core 46, which makes
pair with the body molding recess 41 of the stationary mold 40. A
small core 47 is also formed around and at a predetermined spacing
from that core 46. The small core 47 forms a jointing step portion
around the opening of the body. Below the body molding core 46,
there is formed a shallower cover member molding recess 48, which
make pair with the cover member molding core 42 of the stationary
mold 40. Between the body molding core 46 and the cover member
molding recess 48 of the slide mold 45, there is formed a primary
molding sprue 50, which communicates with the body molding recess
41 and the cover member molding recess 48 through a runner 51 and a
gate 52. A secondary molding sprue 53 is formed below the primary
molding sprue 50. From FIG. 3, there are omitted the actuator for
driving the slide mold 45 to slide vertically, the mold clamping
device, the ejector device for ejecting the moldings, the injector
device and so on.
Hollow moldings can be formed by using the aforementioned molds 40
and 45 in the following manner. The molds 40 and 45 are mold
clamped at a first position, as shown in FIG. 3A. Then, a body
molding cavity Kh is formed by the body molding recess 41 of the
stationary mold 40 and the body molding core 46 of the slide mold
45. Moreover, a cover member molding cavity Kf is formed by the
cover member molding core 42 of the stationary mold 40 and the
cover member molding recess 48 of the slide mold 45. Molten resin
is injected from the primary molding sprue 50. Then, the molten
resin is poured through the runner 51 and the gate 52 into the body
molding cavity Kh and the cover member molding cavity Kf as shown
in FIG. 3B. By this primary molding operation, a body H and a cover
member F are molded to have a jointing half groove M' around their
openings. This half groove M' is shown in FIG. 3C.
Awaiting the cooled solidification, the mold is opened while the
body H being left in the stationary mold 40 and while the cover
member F being left in the slide mold 45. Then, the slide mold 45
is slid to the secondary molding position, at which the openings of
the body H and the cover member F register with each other. This
registering position is shown in FIG. 3C. The molds are mold
clamped at the registering position. Then, a jointing cavity M is
formed by the half grooves M' and M' at the outer circumference of
the abutting portions of the body H and the cover member F, as
shown in FIG. 3D. A resin identical to or difference from the body
molding resin is injected from the secondary molding sprue 53. By
this second molding, the body H and the cover member F are
integrated to produce a hollow molding.
The hollow molding having a thin film on its inner surface is also
obtained, as described hereinbefore, by molding the body portion
and the cover member by the primary molding operation, by forming
the thin film either on the inner surface of the body portion or on
the inner surface of the body portion and the inner surface of the
cover member, and then holding the body portion and the cover
member abutting against each other and injecting the molten resin
to integrate them by the secondary molding operation. In the
aforementioned embodiment shown in FIG. 1, the body molding core
11, the cover member molding core 25, the first and second body
molding recesses 33 and 34, the cover member molding recess 12 and
so on are also formed to have the shape, as shown in FIG. 3, or the
joint portion of the primary molding is made to have a structure,
as described in Japanese Patent No. 3,326,752 and Japanese Patent
No. 3,047,213, but it is simplified in shape and is schematically
shown in FIG. 1.
Referring to schematic FIG. 2, a molding example of a hollow
molding having the thin film on the inner surface is described by
using the stationary molding 1 and the movable mold 20 of the
embodiment shown in FIG. 1. Here in FIG. 2: a blank ellipse
indicates an unfilled cavity; an ellipse with a circle indicates a
filled-up cavity or a semi-finished molding obtained by the primary
molding; a hatched ellipse indicates a semi-finished molding
deposited; and a hatched thick ellipse indicates a hollow molding
having a deposited inner surface. Moreover, FIG. 2 shows only the
slidably driven movable mold 20, but not the fixed stationary mold
1.
The movable mold 20 is slid to a first molding position. Moreover,
the vertically sliding mold 30 is slid to the lower first molding
position. Then, the first body molding recess 33 of the vertically
sliding mold 30 comes into registration with the body molding core
11 of the stationary mold 1 thereby to form a cavity for molding
the cup-shaped body portion. The molds are mold clamped, and the
molten resin for the primary molding operation is injected. As a
result, the first body portion is molded. This state is shown in
FIG. 2A.
Awaiting the cooled solidification of some extent, the movable mold
20 is opened, and the vertically sliding mold 30 is driven to an
upper second molding position, as shown in FIG. 2B. Then, the cover
member molding core 25 of the horizontally sliding mold 22 comes
into registration with the cover member molding recess 12 of the
stationary mold 1. The second body molding recess 34 of the
vertically sliding mold 30 also comes into registration with the
body molding core 11 of the stationary mold 1. This registration
state is shown in FIG. 2B. The molds are mold clamped. Then, a
cavity for molding the cover member is formed by the cover member
molding recess 12 of the stationary mold 1 and the cover member
molding core 25 of the horizontally sliding mold 22, and a second
body molding cavity is also formed by the body molding core 11 and
the second body molding recess 34. The first molding molten resin
is injected into those cavities. By these primary molding
operations, the second body portion and the first cover member are
simultaneously molded, as shown in FIG. 2C.
Awaiting the cooled solidification, the movable mold 20 is opened
to drive the vertically sliding mold 30 into a lower first
deposition position, as shown in FIG. 2D. Then, the first body
molding recess 33 of the vertically sliding mold 30 comes into
registration with the first depositing recess 3 of the stationary
mold 1. Specifically, the first body portion left in the first body
molding recess 33 is registered with and confined in the first
depositing recess 3. Next, the molds are mold clamped to a
depositing extent.
After this mold clamping, the O-ring 5 of the first depositing
recess 3 can be brought into close contact with and deposited on
the parting line face P of the vertically sliding mold 30. A vacuum
source or an inert gas feeding source, for example, is driven to
set the inside of the first depositing recess 3 in an argon gas
atmosphere of about several to several tens Pa. Then, a negative
voltage is applied to the target, and a positive voltage of plus
several kV is applied to the body portion, so that argon is
discharged and deposited on the inner surface of the body portion.
The deposited state is shown in FIG. 2D. The vertically sliding
mold 30 is driven to the lefthand secondary molding position, as
shown in FIG. 2E. Then, the first body portion, as left in the
first body molding recess 33 after the deposition, is registered
with the cover member left in the cover member molding recess 12 of
the stationary mold 1. The molds are mold clamped, and a molten
resin for the second molding operation is injected. As a result,
the body portion and the cover member are jointed and integrated at
the opening. This state is shown in FIG. 2E. The movable mold 20 is
opened to take out the hollow molding having the thin film on the
inner surface of the body portion. When the molding is taken out,
the first body molding recess 33 of the vertically sliding mold 30
is made cavity, as shown in FIG. 2F.
The molding is taken out, and the molds are mold clamped. Then, a
cavity for molding a third body portion is formed by the body
molding core 11 and the body molding recess 33, and a cavity for
molding a cover member is formed by the cover member molding recess
12 of the stationary mold 1 and the cover member molding core 25 of
the horizontally sliding mold 22. The molten resin for the primary
molding operation is injected into those cavities. As a result, the
third body portion and the second cover member are primarily molded
at the same time. The state thus having finished the primary
molding operation is shown in FIG. 2G.
The movable mold 20 is opened. The vertically sliding mold 30 is
slid to an upper second deposition position. Then, the molds are
mold clamped. Thus, the O-ring 5 of the second depositing recess 4
comes into close contact with the parting line face P of the
vertically sliding mold 30 so that the preparation is made for the
deposition. As described above, the voltage and the gas are applied
to the inside of the second deposition so that the deposition is
made on the inner circumference of the second body portion. The
state thus finished the deposition is shown in FIG. 2H. The
vertically sliding mold 30 is driven to the secondary molding
position, as shown in FIG. 2I. Thus, the second body portion, as
left after the deposition in the second body molding recess 34,
comes into registration with the cover member left in the cover
member molding recess 12 of the stationary mold 1. The molds are
mold clamped, and the molten resin for the secondary molding
operation is injected. As a result, the body portion and the cover
member are jointed and integrated at the opening. The movable mold
20 is opened to take out the hollow molding having the thin film on
the inner surface. The taken-out state is shown in FIG. 2J. Then,
the hollow molding having the thin film on the inner surface of the
body portion is likewise molded.
The invention can be practiced in various manners. It is apparent
that the inner surface of the cover member can also be deposited,
for example, by additionally forming a cover member depositing
recess in the stationary mold 1. It is also apparent that two
hollow moldings having thin films on their inner surfaces can be
concurrently molded if a molding apparatus, as shown in FIG. 4, is
used. The description of this embodiment is not made but omitted
either by designating the same components of the molding apparatus
according to the first embodiment, as shown in FIG. 1, by the
common reference numerals, or by dashing the common reference
numerals indicating the same components. According to this
embodiment, a stationary mold 1' is equipped with two body molding
cores 11 and 11' and two cover member molding recesses 12 and 12'.
Moreover, the horizontally sliding mold 22 of a movable mold 20' is
provided with two cover member cores 25 and 25' and a large relief
recess 26' for relieving the body molding cores 11 and 11'. The
vertically sliding mold 30 is provided with two first body molding
recesses 33 and 33' and two second body molding recesses 34 and
34'. Moreover, first and second depositing recesses 3' and 4' of
the stationary mold 1' are so sized as to cover the two first body
molding recesses 33 and 33' and the two second body molding
recesses 34 and 34' of the vertically sliding mold 30
simultaneously. It is further apparent that three or more hollow
moldings having thin films on their inner surfaces can also be
produced by increasing the numbers of the body molding cores and
the cover member molding recesses. It is also possible to make the
body molding resin material and the cover member molding resin
material different at the primary molding time. For example, the
cover members can also be molded of a transparent lens material,
when the hollow moldings having the thin films on their faces are
front lamps or tail lamps.
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